A TYPO3 integrator is responsible for the correct configuration of the
TYPO3 system. Usually, an integrator has administrator privileges and
logs in to the backend from time to time or regularly. If a user with
administrator privileges accesses the system, TYPO3 CMS triggers some
basic system checks and shows an error or warning message in a box
right after the login.

These checks are for example: administrator user name and password
(e.g. does the user still use the default password?), Install Tool
password, etc.

If you, as an TYPO3 integrator, should ever come across those
warnings, react immediately and update the appropriate setting (e.g.
change the password).